Approximation of  Fourier Series of a function  of Lipchitz class by Product Means

U.K. Misra; Subrata K Sahu; D. Acharya; P.C. Nayak

U.K. Misra Department of Mathematics, National Institute of Science and Technology, Pallur Hills-761008, Odisha, India
Subrata K Sahu National Institute of Science and Technology, Ganjam, Odisha, India
D. Acharya National Institute of Science and Technology, Ganjam, Odisha, India
P.C. Nayak Bhadrak (Autonomous) College, Bhadrak, Odisha, India

Keywords: Degree of Approximation, class of function, product mean, Fourier series, Lebesgue integral .

Abstract

Lipchitz class of function had been introduced by McFadden [8]. Recently dealing with degree of approximation of Fourier series of a function of Lipchitz class Nigam [12] and Misra et al.[9,10,11] have established certain theorems. Extending their results, in this paper a theorem on degree of approximation of a function by product summability has been established.

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